As for future scenes they could start by showing wolverine and Rogue working ogether similar to how Kitty and wolverine did In original storyline except Rogue is free with wolverine.
Just Imagne the drama of seeing Magneto played By Ian Mckellan In camp like we have seen as boy In X_Men/first Class.You have possiblty of still seeing
Mystique by his side(they might just allow Rebecca Romijn to be blonde and not try to give powerless mystique dark hair like In Last Stand)
Jean and Cyclops might fill the roles of Rachel and Franklin did In original story.
In original story the escape from camp didn't get a lot of showing.That won't be case here.In comics Magneto sacrificed himself.Just Imagne a regaining powered Magneto against a group of sentinles.
The major question remains.who Is the time traveler.Once we know who It Is
we can speculate better.If they do like In Comics and change minds wiht younger self that leaves us with 3 choices
Now If someone Is actully physically transported to past I think we are looking at 4 possibltys
2:Rogue(If filming begin In spring they might be able to have Anna Paquin In
decent size role once true Blood's new season wraps)
3:Jean(helping to explain why Famke Janssen was teasing a possable return)
(which they might do to get Halle Berry back)
wolverine's role Is going to depend how much a role Hugh Jackman Is willing to play after wrapping the Wolverine.He could very well only want to do a small role meaning they keep him confined to future scenes.
Besides the extact Time travler Is the big question for me Is how will this be structured.will they cut back and forth like the original story or just have a future prologue.
I think It would be Intresting If they end the film without revealinng if the future Is prevented.